Calculator
What the Image Quality Adjuster does
Image Quality Adjuster: compress, resize, or convert images in-browser. Everything runs in your browser and the file is never uploaded.
The Image Quality Adjuster calculates the file you choose without uploading it anywhere. Processing is local, so speed depends on your machine rather than someone else’s server load.
Most people who open the Image Quality Adjuster are someone converting between formats. Sending a photo to a server just to resize it is more exposure than the task deserves.
Your data stays on your machine. Once the page has loaded you could disconnect entirely and it would still work.
Further down the page: what each field expects, how the result is derived, and one example worked from the defaults.
What do the Image Quality Adjuster fields mean?
The Image Quality Adjuster uses 4 inputs. Pre-filled inputs double as documentation: each one shows what a reasonable value looks like.
| Field | What to enter | Default |
|---|---|---|
| Image file | stays on your device | none |
| Max dimension (px) | choose from Original, 512px, 1024px, 1536px or 2048px | 1024px |
| Quality % | accepts 10 to 100 | 80 |
| Format | choose from WebP, JPEG or PNG | WebP |
How does the Image Quality Adjuster work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same calculation.
Range checks come first, so the formula only ever sees values it can handle.
What a typical run looks like
You provide: Image file, Max dimension (px), Quality % and Format
What happens: the file is read into memory by your browser, processed locally, and offered back as a download. It is never uploaded.
You get back: the result as a file you can save, with a one-line summary beside it.
Nothing queues behind a server, so the wait is your device working, and the size limit is set by memory rather than by an upload cap.
Read next: JPEG, PNG, WebP or AVIF: Choosing an Image Format
How to use it
- Choose your file under Image file, or drag it onto the drop area.
- Pick a value for Max dimension (px): the options are Original, 512px, 1024px, 1536px or 2048px.
- Fill in Quality % (10 to 100).
- Pick a value for Format: the options are WebP, JPEG or PNG.
- Press Process Image.
- The results panel then shows Status.
- Copy Link puts the current inputs in the URL, so bookmarking it brings the same numbers back.
What this tool does not do
- EXIF metadata may be dropped during processing, which is usually desirable but worth knowing.
- Re-encoding a lossy format such as JPEG always loses some detail, even at maximum quality.
- It cannot flag an input that is technically valid but wrong for your case.
- Check that each figure is in the unit the label asks for; that is the most common source of a wrong result.
- Because everything runs locally, processing speed depends on your device rather than our servers.
Frequently asked questions
The form asks for Image file, Max dimension (px), Quality % and Format. Every box already holds a working value, which means a single edit is enough to get a meaningful answer.
Quality % accepts 10 to 100. Values outside that range are rejected with a message naming the field, rather than producing something that looks valid but is not.
Your file stays on your machine. Nothing is transmitted, stored or queued for processing elsewhere.
No. There is no account, no usage cap and no trial period. The site is funded by advertising rather than by charging for the tools.
Full double precision is used throughout; only the displayed figure is shortened.